You may want to stop the real-time scanner when you perform system maintenance tasks. When you stop the real-time scanner, it will not start again in the current session unless you do it manually, after a reboot of your computer real-time scanner will be activated again. You can stop/start the real-time scanner by right clicking the VIRUSfighter icon in the system tray and choose Deactivate real-time scanning, you can activate it here again.